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Due to their lightness and simple connectivity, steel racking systems are typically considered as “low-dissipative” structures, which is reflected in the modern seismic codes by the absence of capacity design and the adoption of low behaviour factors. This limited capability of stress redistribution significantly increases the vulnerability of racks under beyond-design seismic hazards and raises the demand for more resilient designs. Along these lines, the proposed Plastic Ovalization Strategy (POS) attempts to increase the ductility of the individual upright frames comprising the cross-aisle direction of racks, and at the same time to preserve their low-cost and easy-to-assemble nature. This is achieved by tasking the bearing failure mechanism of the diagonal bolt hole to absorb seismic deformations, while capacity design is employed to keep the rest of the structure in the elastic zone. Following a detailed discussion on the motives and basic principles of the strategy, two high-rise racking systems are designed twice by professional engineers, once using standard approaches and then by additionally employing the proposed POS rules. Finally, the two design solutions are compared by conducting a comprehensive seismic assessment, which employs a phenomenological macro-model comprising elastic elements and nonlinear springs to simulate the bearing failure mechanism.

There is a strong need to develop eco-sustainable agricultural techniques to improve crop yields while preserving biomolecule contents and reducing the adverse environmental impact of agro-chemicals. The use of microorganisms in agriculture represents an attractive and innovative solution. Herein, a chemical study on the nutritional and sensory qualities of San Marzano Cirio 3 (SMC3), Corbarino (CO) and Brandywine (BW) tomato varieties cultivated with and without effective microorganisms (EM) is reported. LC–MS analysis of the methanolic extracts allowed for the identification of 21 polyphenol derivatives. In different proportions among the studied varieties, the two main polyphenols were rutin and naringenin chalcone; the latter was isolated and chemically identified by complementary HR-ESIMS/MS and NMR methods. SMC3 and CO were richer in naringenin chalcone. Conversely, BW showed higher proportions of rutin; however, in all cases, the relative amounts of the two polyphenols considered together increased over the other minor components after the EM treatment. The qualitative and quantitative HPLC analyses of taste-active compounds (aspartic acid, glutamic acid, AMP and GMP) revealed a significant difference in aspartic and glutamic acids and ribonucleotide contents according to the cultivation condition (±EM), particularly in BW. This study provides chemical data in support of the use of EM green technology for the cultivation of edible agricultural products, such as tomato preserves, and may even improve nutritional and sensory qualities while safeguarding the environment.

A 34-year-old patient underwent liver transplantation for progressive hepatic failure in the setting of congenital hepatic fibrosis. In past medical history, the patient had undergone splenectomy with proximal Linton’s splenorenal surgical shunt creation for symptomatic portal hypertension with hypersplenism. The patient developed an early allograft dysfunction, with radiologic evidence of a reduced portal flow associated to portal steal from the patent surgical shunt. The patient was successfully treated through endovascular placement of a 30 mm Amplatzer cardiac plug at the origin of the splenic vein.

Trattamento delle fistole rinoliquorali: quando è richiesto un approccio chirurgico multidisciplinare al basicranio?Le fistole rinoliquorali sono una patologia poco comune ma, a causa delle temibili complicanze, potenzialmente fatale. A seconda dell’eziologia, possono essere classificate in traumatiche e spontanee. La diagnosi è sia clinica che radiologica. Negli ultimi tre decenni, il trattamento chirurgico si è molto evoluto, passando da un approccio invasivo intracranico ad un approccio endoscopico endonasale, il quale si è dimostrato maggiormente efficace a fronte di un minore numero di complicanze post-operatorie a breve e lungo termine e della riduzione dei tempi operatori e di ospedalizzazione. La diagnosi ed il trattamento delle fistole rinoliquorali sono da sempre stati alquanto complessi. Le principali problematiche dipendono dalle difficoltà di localizzazione della sede della fistola e, nel caso delle forme spontanee, anche dal corretto inquadramento di eventuali fattori predisponenti e comorbilità. Al fine di ridurre al minimo i rischi di insuccesso del trattamento chirurgico è necessario un approccio gestionale di tipo multidisciplinare. In conclusione, la possibilità di assumere le decisioni terapeutiche nell’ambito di un équipe multidisciplinare dedicata – Skull Base Team –, che si avvalga della presenza di otorinolaringoiatra e neurochirurgo, così come del neuroradiologo e dell’oculista, è fondamentale per localizzare con precisione la sede e delineare le caratteristiche della fistola in modo da ottenere il successo terapeutico. La stretta collaborazione multidisciplinare potrà inoltre permettere lo sviluppo in futuro di nuovi biomateriali in grado di facilitare e standardizzare le tecniche di riparazione multistrato, oggi in gran parte condizionate dalle preferenze del chirurgo.Cerebrospinal fluid (CSF) leak remains a rare condition, characterized by serious complications and potentially fatal. According to different etiologies, CSF leaks may be classified into two main categories: traumatic and spontaneous. Spontaneous fistulas seem to be mainly related to obesity and idiopathic intracranial hypertension. Diagnosis is both clinical and radiological. During the last three decades, surgical treatment has mostly shifted to endonasal endoscopic approach, which widely demonstrated to be more effective than invasive intracranial ones. Post-operative complications, long-term sequelae and hospital stay are strongly reduced thanks to endoscopic approach. The diagnosis and treatment of CSF leaks represent a difficult and challenge task. The main effort seems to be related to the precise localization of the leak. An accurate assessment of both predisposing factors and comorbidities is mandatory in case of spontaneous leaks. However, a clinical multidisciplinary evaluation as well as treatment, is essential to decrease the rate of failure of surgery. The presence of a dedicated instruments, the Skull Base Team, the knowledge of reconstructive materials and techniques represents a decisive result in therapeutical management even if for each patient an effective therapeutic algorithm can be obtained considering the correct leak detection and characteristics. In conclusion the strict teamwork with neurosurgeons, neuroradiologists, ophtalmologists will enable the development also of innovative biomaterials, which could spread and standardize multi-layer techniques, nowadays still related to surgeon preferences.

OBJECTIVE Type 2 diabetes may affect the humoral immune response after vaccination, but data concerning coronavirus disease 19 (COVID-19) vaccines are scarce. We evaluated the impact of diabetes on antibody response to the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination in older residents of long-term care facilities (LTCFs) and tested for differences according to antidiabetic treatment. RESEARCH DESIGN AND METHODS For this analysis, 555 older residents of LTCFs participating in the GeroCovid Vax study were included. SARS-CoV-2 trimeric S immunoglobulin G (anti-S IgG) concentrations using chemiluminescent assays were tested before the first dose and after 2 and 6 months. The impact of diabetes on anti-S IgG levels was evaluated using linear mixed models, which included the interaction between time and presence of diabetes. A second model also considered diabetes treatment: no insulin therapy (including dietary only or use of oral antidiabetic agents) and insulin therapy (alone or in combination with oral antidiabetic agents). RESULTS The mean age of the sample was 82.1 years, 68.1% were women, and 25.2% had diabetes. In linear mixed models, presence of diabetes was associated with lower anti-S IgG levels at 2 (β = −0.20; 95% CI −0.34, −0.06) and 6 months (β = −0.22; 95% CI −0.37, −0.07) after the first vaccine dose. Compared with those without diabetes, residents with diabetes not using insulin had lower IgG levels at 2- and 6-month assessments (β = −0.24; 95% CI −0.43, −0.05 and β = −0.30; 95% CI −0.50, −0.10, respectively), whereas no differences were observed for those using insulin. CONCLUSIONS Older residents of LTCFs with diabetes tended to have weaker antibody response to COVID-19 vaccination. Insulin treatment might buffer this effect and establish humoral immunity similar to that in individuals without diabetes.

This paper presents a mechanical model developed for the simulation of the monotonic behaviour of Steel frames with Reinforced Concrete infill Walls (SRCW). In particular, it deals with a specific typology of SRCW, obtained from the classical one through the interposition of dissipative elements in the columns and by stiffening and shaping the steel frame’s corners in a way to prevent the brittle failure of the concrete in compression. This system has demonstrated in past researches to be able to overcome the typical problems of SRCWs and to assure, through a capacity design approach, a global ductile behavior. The selection of the main components to be included in the model is carried out on the base of the analysis of the available experimental tests and of the results of accurate 3D Finite Element model analyses. The behaviour of each component is represented though consolidated models present in the current state-of-the-art and, where necessary, calibrated using the results of the experimental and numerical analyses. The capacity of the proposed mechanical model in representing the global behaviour of the SRCWs is finally demonstrated comparing the results in terms of force–displacement curves with the ones obtained through the refined 3D Finite Element models.

The present paper focuses on traffic load definition for road bridge design according to past Italian codes. In particular, starting from the first code of ’33 up to the current Technical Standard for Constructions (NTC2018), several different approaches have been assumed by the codes. Hence, a historical review is firstly proposed and each code is analyzed together with the proposed load schemes. Such a review has allowed the definition of a parametric investigation on typical Italian r.c. decks. In particular, bending moments due to the traffic loads for which the bridges were conceived are investigated, and thus a preliminary estimation of past-to-current design bending moment ratios is carried out with reference to continuous beams.

Automated Multi-Depth Shuttle Warehouses (AMSWs) are compact storage systems that provide a large surface occupation and therefore maximum storage density. AMSWs represent the future of storage technology, providing substantial savings in terms of cost, space, and energy with respect to traditional warehouses. Currently, designers refer to the standard building codes for the seismic design of AMSWs. Since structural characteristics of AMSWs are considerably different from the steel structures of typical buildings, this current approach used by designers is questionable in terms of safety and efficiency. In this article, the behavior of 5 AMSW structures has been studied performing 150 time-history analyses by direct integration including P-Delta effects. Demand/capacity ratios calculated for each element showed the dominance of the brittle failure mechanism in AMSWs subjected to low-to-moderate seismic actions. These mechanisms mainly took place in upright columns and their base connections prior to the activation of ductile energy dissipation mechanisms of the structure. Based on the results, further improvements have been recommended for the future design provisions, which may lead to a safer seismic design of AMSWs.

The seismic retrofit design of structures in which the bracings are compressed due to the presence of significant vertical loads shall take into account the strong asymmetric working conditions of the bracings induced by the seismic action. The initial compression and the consequent asymmetric cyclic loading lead, indeed, to poor global performances and drawbacks in the case of seismic retrofitting through the substitution of the existing bracings with dissipative ones. In order to overcome such issues, this paper presents the development of an asymmetric re-centering dissipative device characterized by a different behavior in tension and in compression and by a strong re-centering capacity, making it suitable to resist and dissipate the energy generated by asymmetric cyclic loadings. The paper firstly analyzes the specific issues of structures in which the bracings work in strong asymmetric loading conditions due to the presence of significant vertical loads, highlighting the main problems that can arise adopting traditional dissipative bracings. Then the proposed device is conceptually described and its behavior experimentally assessed. Finally, the structural behavior of a sub-system equipped with the proposed device is assessed through numerical analyses. The experimental and numerical results show the effectiveness of the proposed device in reducing the residual displacements and protecting the other structural elements demanded to resist to the vertical loads.

INTRODUCTION AND OBJECTIVE:There has been a significant development of minimally invasive surgical techniques (MISTs) for the treatment of BPH. Prostatic artery embolization (PAE) is one of the mos...

The paper presents data achieved during an experimental test campaign executed on real-scale one storey/one bay EBF steel structures with vertical and horizontal links. Experimental tests were executed in displacement control by applying cyclic loading histories following ECCS45 protocol and constant amplitude-imposed displacements. Data provide indications concerning the energy dissipated by each prototype during tests, the corresponding shear force - angular distortion curves of the dissipative link and, besides, the force-displacement behavior of the steel prototypes until failure.

The use of structural adhesive for the bonding of steel-to-glass elements increased along with the structural and aesthetic requirements of high-performance transparent building skins, providing better performance of the steel-glass assembly reducing the stress concentration in the glass ply. However, the behavior of bonded joints subjected to high temperatures and the alteration of their mechanical characteristics after a heating process are fields that need to be deepened. The present paper aims at providing an innovative contribution to the gap in the knowledge of the behavior of bonded joints at ambient temperatures up to 300 °C. A detailed overview of the test set-up followed by the results of the mechanical tests will be provided. The tests are composed of two main steps that are namely the heating at different temperatures of the joint specimens and the definition of the residual capacity of the joint, under tear or shear load. A comparison of the mechanical behavior will be provided for different structural adhesives: commonly used adhesive DC993, SG20, SG500, and SIKA265 characterized by a soft elastic modulus, and TSSA, a high strength structural glazing silicone film adhesive. The test allows proposing residual resistance criteria that, even if they are obtained for a specific type of steel-glass joint, provide useful information about the choice of the adhesive in cases in which high temperatures are expected. Finally, a finite model is calibrated on the basis of the experimental results, supplying information about the possible modeling choices and the influence of the specific geometry adopted in tests on the results.

The management of portosystemic shunts in liver transplant recipients relies on appropriate perioperative study. There are several strategies for shunt handling, ranging from preoperative interventional procedures to intraoperative surgical interruption or embolization. Appropriate management often results in a successful outcome, although wrong decisions could lead to serious consequences. Here, we report a liver transplant recipient with grade 2 portal vein thrombosis associated with 2 large portosystemic shunts (coronary and mesocaval), which were managed intraoperatively via thrombectomy without shunt ligation. Acute portal vein thrombosis developed early after transplant due to portal steal syndrome. The patient underwent a successful endovascular shunt embolization, with prompt restoration of hepatopetal portal flow and resolution of the portal steal. Use of interventional radiology in perioperative management of transplant patients has recently gained wider importance; our case reported here is particularly suggestive of the good outcomes of a multidisciplinary approach to a threatening complication such as postoperative acute portal vein thrombosis.

This paper studies the influence of the shear studs distribution, in terms of local and global effects, on the behavior of dissipative hybrid Steel frames with Reinforced Concrete infill Walls (SRCWs). Dissipative SRCWs have been recently proposed as seismic resistant systems, capable of coupling the high stiffness of reinforced concrete walls with the advantages of dissipative systems, in which the energy dissipation takes place in localized and replaceable elements. However, experimental tests showed that the global behavior and the failure mechanism of such systems are strongly influenced by the shear studs distribution along the steel frame—reinforce concrete wall interface. In this paper, this issue is studied through suitable numerical models, calibrated on the base of the available experimental results. Several modeling options and strategies are considered and their influence on the final results has been assessed. The resulting numerical model is used to analyze the mechanical behavior of such system and to perform parametric analyses varying the shear studs distribution. The results obtained help the understanding of the mechanical behavior and of the resisting mechanisms activated on the studied system, supplying relevant information for the development of more accurate design rules.

Non-Destructive Testing methods are key tools for the proper characterization of existing constructions and for their reliable structural assessment. Even if several sophisticated methods are currently available, the possibility of using them strongly depends on the analyzed structural typology. This is particularly true for some specific classes of structures like pre-stressed reinforced concrete ones, for which very few methods exist for the evaluation of the residual pre-stressing force in the elements. Moreover, most of them are currently under development, even if this is a crucial information for their structural analysis and assessment. The paper presents a new Non-Destructive Testing method based on the innovative application of X-ray diffraction for the assessment of the tensile force present in pre-stressing wires and strands. The method is firstly conceptualized considering the main features of the X-ray diffraction and the specific issues related to the geometry of the strands, such as the presence of intertwined spiral wires. The method is then formalized proposing a detailed procedure for the estimation of the total tensile force present in the pre-stressing wire or strand on the base of the X-ray diffractometer measurements and of the nominal geometrical and mechanical properties of the element. Finally, an extensive experimental campaign is used to assess the effectiveness of the proposed procedure. The results show the optimal agreement between the tensile force estimated by the proposed procedure and the one effectively applied and allow estimating the measurement error as a function of the tensile force. The in situ tests demonstrate the actual possibility of using the proposed method together with the issues to be still fixed or enhanced.

The evaluation of seismic vulnerability of industrial constructions is a more and more relevant issue considering the damage occurred as consequence of recent earthquakes all over the world. Each industrial construction, on the other hand, has its own peculiarities depending on, for example, age of construction and aging, hosted industrial activities, structural and morphological modifications during its lifetime, and so on. In the present paper the seismic retrofit of an existing industrial steel structure is executed by using a steel self-centering device properly designed. To this purpose, a refined nonlinear model of the structure is developed, taking into account the most relevant aspects such as II order effects, global buckling of the elements, mechanical nonlinearities, etc. The seismic performances of the case study in its current, un-retrofitted, condition are so evidenced through several Incremental Dynamic Analyses. Afterward, the dissipative systems are introduced analyzing the influence on the global behavior of the several parameters defining the flag-shaped hysteretic behavior of the self-centering devices through several parametric nonlinear analyses. Particular attention is paid to the determination of the maximum and residual displacements and to the evaluation of the share of seismic energy dissipated by the dissipative devices and the one dissipated by the gravity structure. The results obtained allow a better understanding of the effects of seismic retrofit intervention through self-centering devices.

This paper presents the results of an extensive experimental campaign on I beam to Circular Hollow Section column joints obtained cutting a dedicated slot on the column through precision laser technology and letting the beam or connection plates pass through the column itself. The application of this technology minimizes the welding necessary to complete the connection, the number and dimensions of the plates, and it assures the continuity of the beam within the column leading to a more favorable mechanical behavior of the joint under vertical loads. Even if the passing-through beam idea was already tested in the past, only recently the laser cutting technology made it really feasible and competitive from a technical and economic point of view. However, several issues about this structural solution needs further clarifications, especially when considering the interaction of the bare steel node with the reinforced concrete slab or the influence of the infill concrete in the column. For this reason, within this research, different joint configurations were designed extrapolating them from realistic case study buildings and testing them under monotonic vertical loads. To deeply understand their behavior, the specimens were designed and realized as four-way joint, differentiating the structural scheme of the joint connecting the main beams and the joints connecting the secondary beams, obtaining a representation of the most common solutions currently adopted in the real practice.

Steel frames with reinforced concrete infill walls (SRCW) are an interesting seismic-resistant structural solution. However, an effective seismic design of SRCWs is not easy due to the current lack of specific capacity design rules that allow controlling the formation of a proper energy dissipating mechanism. In order to overcome such an issue, a ductile design procedure is presented in this paper. The proposed procedure leads to innovative SRCW systems where energy dissipation is expected to take place only in the vertical elements of the steel frame, which are subjected mainly to axial forces. The non-ductile components, i.e. reinforced concrete wall and steel-to-concrete connections, are expected to suffer negligible damage. Accordingly, the system is designed to control the formation of diagonal struts in the infill walls and behaves as a lattice brace instead of a shear wall. Experimental test results and nonlinear finite element analyses are illustrated to support the developed ductile design approach and highlight the advantages of SRCWs.

The paper presents the whole dataset obtained during an experimental test campaign executed on the prototype of a new re-centering dissipative device, characterized by an asymmetric behavior, for the seismic protection of buildings. The experimental tests were performed on two different configurations: on the single prototype of the device (configuration 1) and one in which two prototypes are placed within a steel frame in an inverted V bracings configuration (configuration 2). The experimental tests were executed in displacement control, applying cyclic loading histories. Data are mainly reported in terms of force-displacement cyclic curves for the single prototype in the configuration 1 and for the whole braced system in the configuration 2. Keywords: Dissipative device, Asymmetric hysteretic behavior, Inverted V bracings, Re-centering

Ground penetrating radar is a non-invasive technique that, amongst the various available state-of-the-art methods, is capable of accurately locating both metallic and nonmetallic buried objects. The main object of this paper is to describe the application of a GPR strategy to the non-destructive testing of concrete structures, particularly bridges, where there is a need to identify, quantify and categorize structural reinforcements. The new C-Thrue radar, developed by IDS GeoRadar, was used to investigate two bridges near Pisa (Italy). The acquisition of dense and regular grids was used to provide a full reconstruction of the geometry of the investigated area. Moreover, through the use of sensors in different polarizations, and dedicated data processing techniques, the C-Thrue radar enables the creation of spatially correlated data sets that represent scanned 3-D volumes of the ground, allowing demonstrable benefits in overall assessment of the required structural parameters.

This paper presents the experimental data on the cyclic behavior of Steel frames with Reinforced Concrete infill Walls (SRCW). Two specimens, characterized by a different shear studs distribution, have been tested: the first one is provided with shear studs positioned only in the four corners of the steel frame; the second one presents shear studs all distributed along the perimeter of the steel frame except for the zone of the dissipative fuses. The overall setup, loading protocol, collapse mechanisms, force-displacement curves for both the whole system and the main single components are described for the two tested prototypes.

Background: Thyroid nodules are very common in general population. Even if benign, they may require a treatment in case of symptoms or cosmetic concerns. In the last years, minimally invasive treatments alternative to surgery have been developed, in particular ultrasound (US) guided radiofrequency ablation (RFA).\ud \ud Methods: Twenty-four patients (9 males; 15 females; mean age 57.9 years) were treated and divided in two groups (A and B) according to the RFA needle used (18 gauge needle, AMICA; 17 gauge needle, COVIDIEN). Nodules and patients characteristics, together with procedural data were registered pretreatment and at 1-month follow-up. US visibility of the needle, volume of the nodules, symptoms and cosmetic concerns, complications were registered.\ud \ud Results: Visibility of the needle was not significantly different in the two groups (P=0.0787). At 1 month the mean volume of the nodules dropped from 37.1 to 25 mL in group A and from 23.2 to 15.4 mL in group B; shrinkage rate (36.9% and 39.5%, respectively) was not significantly different (P=0.3137). Symptoms decreased from 3.1 to 1.4 in group A and from 4 to 1.6 in group B: no significant differences in reductions were observed (P=0.3305). Cosmetic score decreased from 3.7 to 3.4 in group A and from 3.9 to 3.6 in group B: no significant differences in reductions were observed (P=0.96). Total complication rate (18.2% in group A vs. 23.1% in group B) did not showed significant differences (P=0.5049).\ud \ud Conclusions: The two systems used in our study resulted equivalent in terms of US needle visibility, efficacy, symptom/cosmetic relief, safety. More patients and a longer follow-up are necessary to confirm our results.